To understand death we must first understand what a human being is. A human being is both spiritual and physical. Humans are spirits clothed with physicality. Paul shows this in 2 Corinthians 5:4:
For while we are still in this tent, we groan, being burdened—not that we would be unclothed, but that we would be further clothed, so that what is mortal may be swallowed up by life.
In his discourse he likens physical bodies to tents or clothing. The longing for the believer is not to be unclothed (that is to be a spirit with no physical body), but rather to be clothed with new physicality, a new body. So humans are spirits clothed with physicality.
We also see that we are spirit and physicality when the Lord raises Jairus’s daughter from the dead:
Luke 8:54-55
But taking her by the hand he called, saying, “Child, arise.” And her spirit returned, and she got up at once. And he directed that something should be given her to eat.
When the child is raised we read that “her spirit returned”. Alive, she is a spirit clothed by a physical body.
This additionally clues us in to what physical death is. In physical death her spirit left her body. Physical death is when the spirit of man leaves his body. The body returns to dust, and the spirit returns to God.
Ecclesiastes 12:7
and the dust returns to the earth as it was, and the spirit returns to God who gave it.
Physical death is a separation of 2 things, the spirit of man and his body. And it is not the way man is meant to be. When God created man, his good design was for man to be body and spirit. Death entered the world because of the sin of our forefather Adam. And now we who are sons of Adam die.
Physical death pictures spiritual death. While physical death is a separation of man’s spirit and his body, spiritual death is the separation of man and God who is spirit (John 4:24). As the body is lifeless and decays without its spirit, so is man without God. As physical death is a mournful thing, so is spiritual death.
Ephesians 2:1
And you were dead in the trespasses and sins
Paul says of people who were physically alive, “you were dead”. He is speaking not of physical death but of spiritual death.
The reality of spiritual death being a separation from God is indicated throughout the scriptures. When Adam and Eve sin, in their sin they seek to hide from God.
Genesis 3:8
And they heard the sound of the LORD God walking in the garden in the cool of the day, and the man and his wife hid themselves from the presence of the LORD God among the trees of the garden.
So begins their death. They separate themselves from God. But not only do they separate themselves, they are also cast away by God and His tree of eternal life. God separates them from His garden, his dwelling place with man, and from eternal life.
Genesis 3:23-24
therefore the LORD God sent him out from the garden of Eden to work the ground from which he was taken. He drove out the man, and at the east of the garden of Eden he placed the cherubim and a flaming sword that turned every way to guard the way to the tree of life.
Adam and Eve were promised death if they ate from the tree, now when they did eat they recieved separation from God’s garden. So here death and separation from God’s paradise are paralleled.
Later God establishes His temple in Israel, that is His new dwelling place with man. Israel is the promised land, a picture of heavenly realities. When Israel sins, they are exiled. They are separated from the presence of God. Again sin which leads to death, is shown to lead to separation from God’s paradise.
The opposite of this for the Christian is spiritual life. This is when the Holy Spirit comes in to man. Rather than separation, God dwells with man.
John 14:16-17
And I will ask the Father, and he will give you another Helper, to be with you forever, even the Spirit of truth, whom the world cannot receive, because it neither sees him nor knows him. You know him, for he dwells with you and will be in you.
At the end of this world, when God makes a new heaven and a new earth, we read in Revelation 21:3-4:
And I heard a loud voice from the throne saying, “Behold, the dwelling place of God is with man. He will dwell with them, and they will be his people, and God himself will be with them as their God. He will wipe away every tear from their eyes, and death shall be no more, neither shall there be mourning, nor crying, nor pain anymore, for the former things have passed away.”
This is the full fulfillment of the dwelling place of God with man. This is the wonderful heavenly reality. Yet we see that some are separated from it. And their separation is called death. It is called the second death, an eternal death, a final separation from the paradise of God.
Revelation 20:14-15
Then Death and Hades were thrown into the lake of fire. This is the second death, the lake of fire. And if anyone’s name was not found written in the book of life, he was thrown into the lake of fire.
So what is death? Physical death is the separation of the spirit of man from his physical body. Spiritual death is the separation of man from God. This begins when man is still physically alive, but if he does not believe in Jesus in his physical life, this continues into a final eternal separation from the paradise of God.
